In a wideband code division multiple access (WCDMA) system, one or more transmission technologies, such as an R99 transmission technology and a high speed downlink packet access (HSDPA) transmission technology, may be configured for one user equipment (UE). An uplink transmit channel in the R99 transmission technology mainly includes a dedicated physical control channel (DPCCH). An uplink transmit channel in the HSDPA transmission technology mainly includes a high speed dedicated physical control channel (HS-DPCCH). The user equipment sends data to a network side by using a configured transmission technology, to implement communication between the user equipment and the network side. However, when transmit power at which the user equipment sends data to the network side is relatively high, quality of data sent by the user equipment is affected, and other users are interfered; therefore, transmit power of the user equipment needs to be controlled.
At present, a process of controlling transmit power of user equipment may be: calculating, by the user equipment, a gain factor of an HS-DPCCH according to a gain factor of a DPCCH and a ratio between the gain factor of the HS-DPCCH and the gain factor of the DPCCH; calculating total uplink transmit power of the user equipment according to the gain factor of the DPCCH and the gain factor of the HS-DPCCH; and when the total uplink transmit power of the user equipment exceeds maximum allowed transmit power, reducing the gain factor of the HS-DPCCH according to the maximum allowed transmit power, to reduce transmit power of the HS-DPCCH, so that the total uplink transmit power of the user equipment does not exceed the maximum allowed transmit power.
Because the user equipment communicates with the network side by using a cell accessed by the user equipment, when the user equipment is in a soft handover area, which is an overlap coverage area of multiple cells, the network side may further configure a dedicated physical control channel 2 (DPCCH2) for the user equipment. In this case, if the user equipment still reduces the gain factor of the HS-DPCCH according to the foregoing method by using the gain factor of the DPCCH, a calculation error occurs; as a result, control accuracy of transmit power is reduced.